Trane LO manual Tracer ZN.520, Fan Switch On/Cancel Buttons, UNT-IOM-6

Fan Switch

On/Cancel Buttons

UNT-IOM-6

Tracer® ZN.520

These setpoint limits only apply to the occupied and occupied standby heating and cooling setpoints. These setpoint limits do not apply to the unoccupied heating and cooling setpoints stored in the controller’s configuration.

When the controller is in unoccupied mode, it always uses the stored unoccupied heating and cooling setpoints.The unit can also be configured to enable or disable the local (hardwired) setpoint. This parameter provides additional flexibility to allow you to apply commu- nicated, hardwired, or default setpoints without making physical changes to the unit.

Similar to hardwired setpoints, the effective setpoint value for a communicated setpoint is determined based on the stored default setpoints (which determines the occupied and occupied standby temperature deadbands) and the controller’s occupancy mode.

The zone sensor fan switch provides the controller with an occupied (and occupied standby) fan request signal (Off, Low, Medium, High, Auto). If the fan control request is communicated to the controller, the controller ignores the hardwired fan switch input and uses the com- municated value. The zone sensor fan switch input can be enabled or disabled through configuration using the Rover service tool. If the zone sensor switch is disabled, the controller resorts to its stored configu- ration default fan speeds for heating and cooling, unless the controller receives a communicated fan input.

When the fan switch is in the off position, the controller does not control any unit capacity. The unit remains powered and all outputs drive to the closed position.Upon a loss of signal on the fan speed input, the controller reports a diagnostic and reverts to using the default fan speed.

Momentarily pressing the on button during unoccupied mode places the controller in occupied bypass mode for 120 minutes. You can adjust the number of minutes in the unit controller configuration using Rover service tool. The controller remains in occupied bypass mode until the override time expires or until you press the Cancel button. Communication jack

Use the RJ-11 communication as the connection point from Rover™ service tool to the communication link—when the communication jack is wired to the communication link at the controller. By access- ing the communication jack via Rover™, you gain access to any controller on the link.

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